8-Bit Theater: When loser sociopath Black Mage unexpectedly finds himself without his despised bunch of "allies" (aka The Light Warriors), he enjoys the freedom from their quest to fulfill his lifelong dream of... becoming a cobbler's apprentice. After murdering the previous owner of a cobbling shop (the man made the mistake of rebuffing Black Mage's application), Black Mage takes over as the new owner. (The amazing thing, knowing Black Mage, is he did ask beforehand, but the more amazing thing is that he actually sticks with the job.) Turns out, he is surprisingly good at making shoes. Something of a wasted talent, what, with all his usual plans for death and destruction and sacrificing orphans to the Dark Gods, that is.
In true Black Mage form, though, he does make shoes out of the COBBLER HE SLAUGHTERED.
In Clan of the Cats, Dracula has been revived after years of being dead. The first thing he does is...go shopping for Dracula memorabilia.
Invoked by Kria multipletimes as a way to spend time with and comfort some of the less murderous people she associates with.
Regina and Dark Pegasus bicker over hand lotion. The author lampshades in the comment box that " I cannot deny I have a special love for just dropping in on characters at very mundane moments in their lives. It amuses me to no end."
In Everyday Heroes, Mr. Mighty steps out his of front door one morning to find his arch-nemesis, Dr. Unpleasant, volunteering as a school crossing guard.
The entire point of The Last Days of FOXHOUND, which mostly shows the titular group when they aren't performing super duper top secret missions or plotting global revolutions.
At one point, Sniper Wolf gets her prescription for Tranquilizers refilled.
A Miracle of Science has a variation: the villain is seen doing things such as pruning his plants or conducting an orchestra, but it's always for the purpose of improving his machines (e.g. the pruning is a performance test for a motion controlled robot), as his Science-Related Memetic Disorder makes it impossible for him to do anything that isn't related to his obsession; he may be out shopping, but he's only shopping for things that will assist his plans.
Inverted later when Nale comments on the dedication of the heroes, then the story cuts to them playing Parcheesi (although Belkar - who is a short order of Sociopathic Hero, with extra sociopath and hold the hero - joins in, so it's still kind of a straight example).
In the prequel Start of Darkness, the then human Xykon enjoyed coffee. One of the reasons he descended into full Ax-Crazy evil is that being turned undead robbed him of his sense of taste, meaning he couldn't enjoy coffee anymore.
The whole point of the "Meanwhile In The Dimension Of Pain" Filler Strips in Sluggy Freelance was to show what the Dimension of Pain demons (who try to steal Torg's soul every Halloween) do the other 364 days of the year. Even when the demons return to canon strips for the "That Which Redeems" arc, we still see them take breaks from slaughtering the human race to do more mundane things, like shopping (albeit for pre-packaged human souls).
We first meet Butterfly in Collar 6 when she's out walking her slave.
Chapter 14 of Evil Plan begins by showing a "fourit" imageboard discussion on current affairs. It's revealed that Anguish, the most respected villain in the series, enjoys spending his time on this universes' version of 4chan in an astonishingly normal manner.
Slightly Damned: When waiting for Moonshade's signal to attack the city, the demons are engaging in the St.Citrus flower festival. In particular we see Psycho for Hire Azurai eating a drumstick and wearing a new hat (which he got by killing a guy when he wasn't supposed to) and Iratubuying booze, which he pays for using money taken from an old couple Azurai earlier killed.
Homestuck has a very on the nose example when Diamonds Droog, a villainous member of the Midnight Crew gang, gets teleported to next week by an enemy and finds himself grocery shopping.